110results about How to "Avoid calling the police" patented technology

The invention discloses a method, device and equipment for avoiding repeated alarms in a human body inspection and quarantine system. The method for avoiding repeated alarms in the human body inspection and quarantine system comprises the following steps that infrared video image data and visible light video image data of a human body are acquired, and heating personnel in the infrared video imagedata are measured by using an infrared thermal imaging temperature measurement method; when the heating personnel are monitored, a face image area of the heating personnel in a visible light video image is detected by using the matching relationship between an infrared image and the visible light image, and whether the face image area is tracked or not is judged; if the face image area is not tracked, screenshots of the face image area are saved, an alarm is given, and the face image area is tracked at the same time; and if the face image area is tracked, no alarm is given. The human body inspection and quarantine system is prevented from repeatedly alarming the same alarm personnel.

A rapid early-warning system based on a phase-sensitive optical time-domain reflectometer includes a disturbance monitoring and positioning module, and a disturbance signal identifying module. The disturbance monitoring and positioning module: a disturbance monitoring part performs difference on the beat signal intensity of a phase-sensitive optical time-domain reflectometer, the rapid early-warning system based on the phase-sensitive optical time-domain reflectometer can monitor the difference of the beat signal intensity all the time, and once the difference of the beat signal intensity changes, it means that a disturbance signal generated by disturbance occurs; and a positioning module can determine position information of a disturbance point through the time difference of an optical time-domain reflectometer echo. The disturbance signal identifying module includes a pre-treatment module, a feature extraction module, a template training module, a pattern classification module, and a post-treatment module; template training means that templates of a plurality of types of signals can be constructed according to features of a series of different types of disturbance signals; the features of the disturbance signals and preset templates of the plurality of types of signals are matched, and the types of the signals can be determined according the matching degrees; and a warning measure or a no-warning measure can be preformed according to a result of pattern classification.

The invention discloses a method used for inquiring a thrown object vehicle and a system thereof. The method comprises the following steps of according to a video sequence in a monitoring area, detecting a thrown object event; searching a video frame in which a thrown object and a vehicle appear at the same time in the video sequence; and extracting vehicle information from the video frame in which the thrown object and the vehicle appear at the same time so as to determine the thrown object vehicle. The method and the system can adapt to complex and changeable conditions of outdoor road scenes, the thrown object event can be rapidly and accurately detected, false object alarm is effectively avoided, and according to the thrown object event, through reversely traversing and monitoring a video sequence, a target thrown object vehicle is accurately inquired.

The invention discloses an alarming method for a device. The device comprises at least one component, wherein each component comprises a plurality of parts. The method comprises the steps of receiving vibration or rotation monitoring data in device operation; calculating a plurality of characteristic index values from the monitoring data, wherein the characteristic index values include first characteristic index values and second characteristic index values; according to a second characteristic index value associated with a specific part, calculating a state score of the part; according to a first characteristic index value associated with a specific component and a second characteristic index value of a part contained in the specific component, calculating a state score of the component; according to the first characteristic index values of all the components and the second characteristic index values of all the parts comprised in the device, calculating a state score of the device; and according to the state score of the part, the component or the device, determining an alarm level of the part, the component or the device. The invention furthermore discloses an alarming apparatus for the device.

The invention discloses an intelligent mower straight line walking control system based on inertial / magnetic sensor MARG attitude detection. The execution mechanism comprises an MARG attitude detection module, a mower main control unit and a motor driving module, wherein the MARG attitude detection module is in charge of real-time calculating the mower attitude information according to sensing data acquired by the MARG sensor; the mower main control unit is in charge of executing a mower heading adjustment control system to control the mower to walk in a straight line according to the calculated attitude information and generating driving control signals for driving the motor; and the motor driving module is in charge of driving the motor to rotate according to the control signals provided by the main control unit. During a straight line walking process in a certain section by the mower, the attitude of the mower is calculated in real time through the sensing data acquired by the inertial / magnetic sensor MARG, the yaw in the attitude angles is used for controlling the heading of the mower, a roll angle is used for judging the road wheel of the mower, and thus, the motor rotation speed when the mower carries out heading adjustment on a slope can be compensated. The straight line walking of the mower can be effectively controlled, the attitude of the mower is detected in real time, roll-over of the mower can be prevented, and a foundation is laid for a parallel reciprocating mowing motion executed by the mower and improved working efficiency.

The invention discloses an air processing device control system based on a cloud platform and a control method of the air processing device control system. The control system comprises air monitoringdevices and air processing devices, wherein the air monitoring devices and the air processing devices are associated with the cloud platform through a network system; and the cloud platform is associated with terminal devices used for controlling the air processing devices to work through the network system. The control method is that the cloud platform controls the air processing devices according to interaction results of the cloud platform and the terminal devices. According to the air processing device control system based on the cloud platform and the control method, great convenience isbrought to a user, namely, the user can control the different air processing devices to work cooperatively at one place; the advantages of the cloud platform are fully utilized, the total production cost of the air processing device control system is greatly reduced, the cost performance of the air processing device control system is greatly improved, and the application and popularization of theair processing device control system are facilitated; the multi-user air processing device control system based on the cloud platform can be realized; and use safety of the system is greatly improved.

The invention relates to an intelligent well lid electronic lock with lid-opening alarming. The lock comprises a main control module, and comprises an outer unlocking electrode module, a lid-opening intelligent identification module, a password authentication module, an unlocking electromagnet, a wireless communication module and an in-built battery module which are separately connected to the main control module. The lid-opening intelligent identification module is connected to an accelerated-speed sensor. The outer unlocking electrode module is used for matching with an outer hand-held unlocking terminal, and providing the main control module with an unlocking signal and an unlocking electromagnet power supply. The main control module determines whether the unlocking signal is a lawfully authorized unlocking signal through the lid-opening intelligent identification module and the password authentication module, if yes, the main control module controls the unlocking electromagnet to unlock the well lid electronic lock, and if not, the unlocking electromagnet is inactivated and the main control module sends a lid-opening alarming signal to a monitoring server in a well lid management center through the wireless communication module so as to alert a manager, thus greatly facilitating operation of an operator, and facilitating in-time notification to the operator to perform related maintenance operation.

The invention relates to a video occlusion detection method for an automobile data recorder. The method comprises an occlusion detection process for obtaining an image sequence composed of a pluralityof video frame images based on continuous sampling, and the occlusion detection process for obtaining the image sequence composed of the plurality of video frame images based on continuous sampling is used for judging whether the sampled image sequence is continuously occluded or not so as to judge whether the video is continuously occluded or not. Whether the whole image is shielded or not is judged by counting the total number of the shielded sub-blocks, so that the misjudgment rate of image shielding is reduced; whether the video is occluded in a time period or not is judged by calculatingand comparing similarity indexes between video frame images before and after a video image sequence, alarm caused by instantaneous occlusion is avoided, meanwhile, false alarm caused by misjudgment of image occlusion is reduced, the accuracy is high, and the robustness is high.

The invention relates to a double-layer circulation system used for the AOI procedure of a PCB. The system comprises a rack, a detected material box circulation vehicle and a to-be-detected material box circulation vehicle are arranged on the lower layer of the rack, a before-cleaning conveying segment and an after-cleaning conveying segment are arranged on the upper layer of the rack, a cleaning machine is arranged between the before-cleaning conveying segment and the after-cleaning conveying segment, the conveying face of a lifting conveying segment is driven by a synchronous liner module to do lifting motion, and therefore the conveying face is switched between the upper operation position flush with the upper layer of the rack and the lower operation position flush with the lower layer of the rack, a transverse moving suction cup set is arranged above the to-be-detected material box circulation vehicle, a six-axis robot is arranged on one side of the robot, a board turning suction plate is arranged at the input end of the before-cleaning conveying segment, and under the selective coordination of the six-shaft robot, the turning plate suction plate carries out PCB turning. The double-layer circulation system has the beneficial effects that the whole circulation system can more stably work, circulation is more smooth, and meanwhile possibility of alarming and disqualified product appearing is reduced.

The invention relates to an early fire detection method which is used for detecting a fire and comprises the following steps: S1, acquiring a real-time monitoring video; S2, providing a single-frame detection network model, and using the single-frame detection network model to detect whether flame and / or smoke exists in the image at the current moment or not so as to obtain a first detection result; S3, providing a time sequence detection network model, and detecting a flame level and / or a smoke level in the video sequence before the current moment by using the time sequence detection networkmodel to obtain a second detection result; and S4, calculating a fire risk level by combining the first detection result and the second detection result. Thus, missed detection of fire disasters is prevented, and the accuracy of fire detection is improved. The invention also provides a computer readable medium. The invention also provides a detection system.

The invention provides a method for controlling laser cutting, which comprises the following steps: presetting the height of a cutting nozzle deviating from board to be higher one offset height than the height of a normal cutting nozzle in the initial stage; and recovering a laser cutting head nozzle to the height of the normal cutting nozzle after a laser cutting head sensor deviates from the hole slag range distance according to a path movement track. The method for controlling laser cutting can make a laser cutting machine adopt the height of the cutting nozzle deviating from the board in the initial cutting stage and increase the delay time of an alarming sensor, so as to reduce the alarming frequency of collision protection of the cutting track in the initial stage, avoid unnecessary alarm and improve the whole cutting efficiency. A laser cutting machine tool can be favorably guided into the normal cutting state.

The invention discloses a smart watch with an emergency calling function and a smart watch system, belongs to the field of watches and aims to solve the technical problems that an existing smart watchcannot perform emergency calling, and less information is provided for rescue teams. The smart watch structurally comprises a watch terminal, a power module, a clock module and a display screen, thepower module, the clock module and the display screen are arranged at the watch terminal, the display screen is connected with the clock module, the watch terminal is further provided with an audio and video acquisition module, a wireless communication module, a position acquisition module, an alarm module, an emergency calling key and a one-key calling APP (application), the audio and video acquisition module, the position acquisition module and the alarm module can be driven to simultaneously start by triggering the emergency calling key under calling of the one-key calling APP, and the wireless communication module can be called to transmit audio information, video information, current position information and alarm information to a remote alarm receiving center. The system comprises the remote alarm receiving center and a plurality of smart watches with the emergency calling function.

The invention discloses a novel automobile door lock executer mechanism which comprises an executor shell, a safing / de-safing execution arm, a safing / de-safing state micro switch, an electric safing / de-safing device, a mechanical key safing / de-safing device and an anti-theft signal device. A worm gear transmission mode is adopted to replace original multi-stage gear transmission and a micro switch is adopted to replace a conventional sliding piece structure, so that the novel automobile door lock executer mechanism is relatively compact in structure, noise can be reduced, the sensitivity of signal transmission can be improved, and the security can be improved.

The invention relates to the field of perimeter protection safety technologies, and discloses a vibrating-optical-fiber-technology-based perimeter intrusion monitoring system. The perimeter intrusion monitoring system comprises multiple protective zone processing modules and an integrated alarm platform, wherein the multiple protective zone processing modules are arranged in a protective zone, and each protective zone processing module comprises a light emission end, a light receiving end, an optical fiber loop, a comparator and an optical terminal; one end of the optical fiber loop is connected with the light emission end, the other end of the optical fiber loop, after being folded and bent, is connected with the light receiving end, an optical signal sent by the light emission end is fed back to the light receiving end along the optical fiber loop, the comparator compares whether an optical signal received by the light receiving end is consistent with the optical signal sent by the light emission end or not, and transmits an obtained result to the optical terminal, and the optical terminal converts the result, and transmits the obtained result to the integrated alarm platform by a communication optical fiber; and when receiving that the comparison results are inconsistent, the integrated alarm platform gives a prompt alarm, so that the technical problem of not high protection safety existing in perimeter protection measures in the prior art is solved, and then the security of perimeter protection is improved.

The embodiment of the invention provides an identification method, system and device for micro-flow leakage of an intelligent gas meter. The method comprises the steps: determining a first abnormal pulse signal i as an abnormal pulse through judgment, and obtaining the first abnormal pulse time [delta]Ti of the first abnormal pulse signal i; obtaining a second abnormal pulse signal j determined asan abnormal pulse and a second abnormal pulse time [delta]Tj of the second abnormal pulse signal j, wherein the first abnormal pulse signal i is an abnormal pulse before the second abnormal pulse signal j; and if yes, accurately judging whether the second abnormal pulse signal j is a leakage pulse by judging whether the second abnormal pulse time [delta]Tj is smaller than or equal to the first abnormal pulse time [delta]Ti+[delta]t, so that the situation of false alarm can be effectively avoided.

The invention discloses an intelligent alarm and fault diagnosis system for a transformer substation and a scheduling center. According to the system, an alarm is electrically connected with a transformer substation alarm information integrated function module; the transformer substation alarm information integrated function module is electrically connected with a transformer substation alarm information processing function module; the transformer alarm information processing function module is electrically connected with a scheduling center-transformer substation information interaction function module; the scheduling center-transformer substation information interaction function module is electrically connected with a scheduling center alarm information splicing function module; and the scheduling center alarm information splicing function module is electrically connected with a scheduling center intelligent alarm function module. Due to the adoption of the intelligent alarm and fault diagnosis system, the situations that the coordination between centralized diagnosis of the scheduling center and local diagnosis of the transformer substation adopted in a conventional fault diagnosis and intelligent alarm of the transformer substation and the scheduling center is lacked, the practicability of the centralized fault diagnosis function in not ideal, difficulty in rapidly analyzing and positioning exist, false alarm or miss of alarm information occurs, and the like are avoided.

The invention discloses a manufacturing method of a silicon-based MEMS micro nano through hole structure, and relates to the field of realizing methods of silicon through hole structures. The manufacturing method comprises the following steps: depositing a silicon dioxide thin film on the front surface of a silicon substrate material, then performing through hole graph transferring, depositing a metal thin film layer on the back surface of the silicon substrate material, and coating the back surface of the silicon substrate material with a photoresist thin film layer. The through hole graph transferring of the silicon dioxide thin film is performed by a trifluoromethane RIE dry etching method; a pretreatment step of silicon dry etching comprises oxygen RIE etching cleaning and trifluoromethane RIE dry etching cleaning, and then dry deep etching for silicon is performed; the defects of complicated steps, low efficiency, low consistency, low stability and the like of the conventional method for realizing the silicon micro nano through hole structure by dry etching (DRIE or ICP) are overcome; the novel method for realizing dry etching of micro nano on a silicon through hole structure is provided, so that the realizing efficiency of the micro nano on the silicon through hole structure is greatly improved, and the manufacturing precision, the consistency and the stability are also improved.

The invention relates to a method and device for judging failure of a frequency conversion module temperature detecting device. The method includes the following steps that 1, when a system is started, the real-time temperature Tf0 of a frequency conversion module is detected; 2, when the starting duration reaches set time b, the real-time environment temperature T0 and the real-time temperature Tf of the frequency conversion module are detected, and the temperature increment delta Tf of the frequency conversion module is calculated according to the formula delta Tf=Tf-Tf0; 3, the normal temperature variable c of the frequency conversion module is determined according to the real-time environment temperature T0; 4, the temperature increment delta Tf of the frequency conversion module is compared with the normal temperature variable c of the frequency conversion module to judge whether the frequency conversion module temperature detecting device fails or not. By means of the method, whether the frequency conversion module temperature detecting device goes wrong or not can be judged before the temperature of the frequency conversion module becomes the highest, it is avoided that an alarm cannot be given before the frequency conversion module is heated to the safety temperature because the frequency conversion module cannot be detected, and therefore damage to the frequency conversion module is avoided.

The invention discloses a multifunctional luggage case burglar alarm and an antitheft method and belongs to the technical field of prevention of burglary. The luggage case burglar alarm utilizes combination of mechanical prevention of burglary and electronic alarm prevention of burglary and comprises an antitheft device, an antitheft controller and an antitheft remote control alarm. The antitheft device and the antitheft controller are installed in a luggage case, and the antitheft remote control alarm is arranged at the master and can transmit and receive a signal by a wireless mode. Under the control of the antitheft controller, the antitheft device can stop luggage case pulleys so that luggage case anti-skid effects are obtained and antitheft effects are obtained when burglary occurs. The antitheft method utilizing the luggage case burglar alarm can determine if burglary occurs according to a sensor signal and give an alarm. GPS positioning information is transmitted to the antitheft remote control alarm so that bidirectional alarming and positioning tracking are realized. The luggage case burglar alarm can monitor abundant information, realize alarming, prevention of burglary, and positioning tracking after burglary, solves the problem that the existing luggage case has a single antitheft function and an easily-broken antitheft unit, and improves antitheft reliability.

The invention relates to a patent foramen ovale suture device and a use method thereof. The patent foramen ovale suture device comprises an outer pipe and an inner pipe, wherein the inner pipe can slide in the outer pipe, a suture line penetrating groove is formed at a center of the inner pipe, two traction needle grooves are symmetrically formed in the inner pipe, the top ends of the traction needle grooves are arc-shaped, guiding blocks are arranged on an end portion of the inner pipe, the edges of the guiding blocks are arc-shaped, and are aligned with the traction needle grooves, elastic traction needles are arranged in the traction needle grooves, the elastic traction needles can slide along the traction needle grooves and the edges of the guiding blocks, clamping holes correspondingto the elastic traction needles are formed in portions, corresponding to the guiding blocks, on an end surface of the outer pipe, line hooks are arranged in the clamping holes, and suture lines are arranged on the elastic traction needles. The patent foramen ovale suture device is used for minimally-invasive surgery suture when a foramen ovale in a heart is patent, and the situation that in a cardiography state of the heart, suture line positions are vague, so that operation is difficult can be avoided, so that the surgery efficiency is effectively improved.

The invention discloses a sealed circulation water cooling device with a conductivity protection function. The device comprises a main circulation loop and a deionization branch. The main circulation loop comprises a main circulation pipe, an electric three-way valve, an air-water heat exchanger and an apparatus to be cooled. The deionization branch comprises an ion tank and a buffer tank. The deionization branch and the main circulation loop interflow at an inlet of the main circulation loop, a bypass is arranged on the main circulation loop, and a normally-open ball valve is installed on the bypass, so that cooling media still exist in the main circulation loop to flow through the normally-open ball valve and the air-water heat exchanger when the electric three-way valve is closed, cooling water in an outer tube of the air-water heat exchanger and in the air-water heat exchanger can be maintained in a flow circulation state during the sealed circulation water cooling device operation for purification, and ultrahigh conductivity alarming caused by stopping of the air-water heat exchanger due to the closing of the electric three-way valve is prevented effectively.

The embodiment of the application provides a power distribution bar monitoring method. The method comprises the following steps: sending power distribution state information of multiple power distribution bars to a monitoring platform by adopting the electric energy of the power distribution bar through a network communication control board; turning on a network communication interface when determining a fact that the target power distribution bar cannot provide electric energy at present, thereby acquiring standby electric energy provided by the monitoring platform through the network communication interface; and sending the power distribution state information of the power distribution bar in serial connection with the target power distribution bar and the power supply alarm informationfor the target power distribution bar by using the standby electric energy, thereby enabling the monitoring platform to display the same. According to the power distribution bar monitoring method provided by the embodiment of the application, the accuracy of the alarm information is improved.

The invention discloses a container type diesel generator set suitable for high-environment-temperature work. The set consists of a diesel engine, a generator, a public chassis, a control system, a cooling water tank, a container, a silencer and the like. The set is characterized by using the advantages of such technologies as air filter direct container external intake, generator direct container external intake and exhaust cooling and top electric multistage water tank cooling; the temperature in the container is reduced through reducing the cooling capacity in the container; the air filter and generator cooling adopts direct intake and exhaust out of the container; the water tank is directly cooled out of the container; and the high-water-temperature warning of the diesel generator set cannot be caused by high temperature in the container due to placement of the diesel generator set in the container so as to enable the diesel generator set to be incapable of operating with full power. The container type diesel generator set has the advantages of low temperature rise in the container, high reliability of the diesel generator set, low power loss and adaptation to high-environment-temperature places.

The invention provides an abnormality alarming device for a UPS (Uninterruptible Power Supply), wherein the UPS is connected with a current input power supply; the abnormality alarming device for the UPS comprises one or a plurality of current sensors, a temperature transmitter, a data acquisition module, a processing module, an executing module and an alarming module; the data acquisition module is connected with the current input power supply through the current sensors; the temperature transmitter is connected with the data acquisition module; the data acquisition module is connected with the processing module; the processing module is connected with the executing module; the executing module is connected with the alarming module. According to the abnormality alarming device for the UPS, a main wire inlet terminal and a standby wire inlet terminal of the UPS are respectively provided with a power supply online monitoring alarming module; when the wire inlet terminals of the UPS are de-energized, the UPS is in fault during the charging process or the temperature is abnormal, field working personnel and working personnel who are possibly not in the field are timely informed of the fault state in the form of sound-light alarm and voice call prompt, the fault is timely found out and solved, and the stability and reliability of a machine room power supply system are guaranteed.

The invention discloses an alarm method for a lock. The alarm method comprises the following steps: when an illegal unlocking instruction input by a user is received, turning on an image acquisition mechanism, and acquiring the face image of the user; counting illegal unlocking instruction input times by the user; judging whether a preset alarm condition is reached according to the acquired face image of the user and the illegal unlocking instruction input times by the user; when the preset alarm condition is reached, acquiring a corresponding alarm mechanism according to the acquired face image of the user and the illegal unlocking instruction input times by the user, and alarming according to the acquired alarm mechanism. The invention further discloses an alarm device for the lock and acomputer-readable storage medium. Through the alarm method and the alarm device for the lock and the computer-readable storage medium, remote control and management of the lock can be achieved, intelligent management of the lock can be achieved, and unsafe factors are prevented from occurring.

The invention discloses large-scale high-temperature test equipment applied to the reliability test of a solid-state disk. The large-scale high-temperature test equipment includes a housing of the equipment. The housing is provided with a plurality of independent aging chambers, and the shell of each housing is provided with a wind circulation system, a temperature control system, an over-temperature protection system and a product power supply system. The large-scale high-temperature test equipment is energy-saving and environmentally-friendly, the power source of each high-temperature chamber can be controlled independently, and the reasonable use of each aging chamber can be individually controlled. Frequent shutdown, starting-up, heating, cooling and other operation of the equipment can be minimized. Compared with other equipment with same production capacity, at least 40% of power consumption is saved. A product test rack adopts a cart-type aging rack, and a cart type design is used. Universal wheels are installed at the bottom of the rack body, and the product test rack is easy to push and pull when in use.

The invention discloses an air inlet device for controlling exhaust gas temperature by waste gas drainage. The air inlet device comprises an intercooler (1), a turbocharger (2), a selective catalytic reduction (SCR) postprocessing device (3) and a drainage pipeline (6); a compressor outlet of the turbocharger (2) is communicated with an air inlet tube of an engine (2) through the intercooler (1); a turbine outlet of the turbocharger (2) is communicated with the SCR postprocessing device (3); an exhaust port of the SCR postprocessing device (3) is provided with a temperature sensor (5); one end of the drainage pipeline (6) is communicated with a turbine inlet of the turbocharger (2); the other end of the drainage pipeline (6) is communicated with the outlet of the intercooler (1); the drainage pipeline (6) is provided with a controlled valve (7); the temperature sensor (5) and the controlled valve (7) are respectively and electrically connected with an engine electronic control unit (ECU) (8). By the air inlet device, the conversion efficiency of a catalyst in the SCR postprocessing device (3) of the engine is improved.

The invention relates to a tension-based electronic fence, which comprises an enclosing wall, and comprises a physical layer which comprises a tension fence unit, a video linkage unit and an alarm unit, and the tension fence unit and the video linkage unit are both connected to the alarm unit; the sensing layer comprises a sensor assembly and is used for detecting the fence units in real time and transmitting detected signals to the fence host; the control layer comprises a fence host and an upper computer used for controlling the fence host, the video linkage unit and the alarm unit; the network layer transmits, analyzes and processes the front-end data of the physical layer in real time through the Internet and a cloud system and uploads the front-end data to an upper computer; according to the electronic fence provided by the invention, various detection means are used at the front end, various sensors form a sensing network, data analysis is carried out through a fusion algorithm, and the accuracy and reliability of alarm are improved.

The invention is applicable in the optical field and provides a Fresnel lens, a passive infrared detector and a security system. The Fresnel lens comprises a plurality of strip-shaped Fresnel lens units which are the same in structure; the plurality of strip-shaped Fresnel lens units are arranged in parallel in turn along a width direction thereof; each Fresnel lens unit comprises an exit surfaceand a smooth incidence surface; an arc-shaped exit region is arranged on the exit surface; a plurality of first concentric circular arc tooth grains are arranged above the arc-shaped exit region in turn along the height direction of the Fresnel lens unit; circle centres of the first tooth grains are superposed with the circle centre of the arc-shaped exit region; the depths of the plurality of first tooth grains are equal; and the distances between every two adjacent first tooth grains are progressively decreased outwardly along the centre of the arc-shaped exit region. Because the arc tooth grains are arranged above the arc-shaped exit region, the effective detection height of the lens within a detectable distance is higher. Because infrared ray emitted by a lower movable object cannot be received by the lens, unnecessary alarm is avoided.